Prophylactic inhaled NO prolongs survival in mice infected with <i>P. berghei</i> ANKA.

<p>Kaplan Myer survival curves are shown for C57BL/6 mice infected with 1x10⁶<i>P. berghei</i> ANKA PEs and treated in (A-C) with either 80 ppm NO (red) or air (black) starting one day prior to infection, or in (D-E) with either nitrite (administered in the drinking water at 500 mg/L of water, shown in red) or water (black). Survival (A and D) was assessed twice daily. Significant differences in survival were assessed by Log rank test. For (A) p = 0.0007, n = 18 in air and n = 20 in NO group, representative of 5 independent experiments. For (D) p = 0.0004, n = 10 per group, representative of 2 independent experiments. Parasitemia levels did not differ between the groups (B and E). Hematocrit did not differ between iNO- and air-treated groups (C).</p

Inhaled NO prevents loss of blood-brain barrier vascular integrity in mice infected with <i>P. berghei</i> ANKA.

<p>(A) Photographs of brains from mice injected with Evans blue on day 6 post-infection. Brains from mice prophylactically treated with air (left panels) and with 80 ppm NO (right panels). The number on the lower left corner is the peripheral parasitemia for that mouse. (B) Quantification of total Evans blue extravasation in the brain as an indication of vascular leak. The line indicates median Evans blue values from uninfected mice. p<0.0001 by Mann-Whitney. n = 15 per group. (C) Number of hemorrhages quantified (blinded to the treatment group) from H&E stained sections of brains collected on day 6 post-infection from mice prophylactically treated with either air or 80 ppm NO. p = 0.0079 by Mann Whitney. n = 5 per group.</p

Inhaled NO reduces systemic inflammation in mice infected with <i>P. berghei</i> ANKA.

<p>Heparinized saphenous vein blood was collected on day 5 post-infection from mice that were prophylactically treated with either air or 80ppm NO. Plasma levels of (A) IFNγ, (B) TNF, and (C) MCP-1 were determined using the mouse inflammation cytometric bead array. Statistical differences were assessed by Mann-Whitney test. For (A) p = 0.0004, for (B) p = 0.0035, for (C) p = 0.018. Data are representative of 2 independent experiments. Plasma from uninfected mice was also tested as a control, and levels of all 3 cytokines were below the limit of detection.</p

Inhaled NO reduces PE accumulation and ICAM-1 expression in the brains of <i>P. berghei</i> ANKA infected mice.

<p>(A) Luminometer imaging of brains collected on day 4 post-infection from mice infected with <i>P. berghei</i> ANKA–GFP–luciferase PEs and prophylactically treated with either air (left panels) or 80 ppm NO (right panels). The rainbow scale represents the relative level of luciferase activity (correlates with parasite load). The numbers on the lower left corner are the peripheral parasitemia levels for each mouse. The bottom panels are brains from a C57BL/6 mouse on the left and a BALB/c mouse on the right. (B) To quantify the brain bioluminescence, total flux (photons per second) was calculated for each brain. p = 0.023 by Mann-Whitney test, n = 17 per group. (C) Immunohistochemistry analysis of ICAM-1 on formalin fixed brain sections from parasitemia matched mice infected with <i>P. berghei</i> ANKA and prophylactically treated with either air (top panels) or 80 ppm NO (middle panels), or uninfected mice (bottom panels). (D) ICAM-1 mRNA expression displayed as copy number was quantified by quantitative real time PCR in the brains of parasitemia matched infected mice prophylactically treated with air or 80 ppm NO. The line represents the median copy number for uninfected mice. p =  0.028, by Mann-Whitney, n = 14 for air, n = 10 for NO.</p